Dozens of people charged as part of a major trans-national police operation targeting organised crime have appeared at the Auckland and Hamilton district courts this afternoon.

In Auckland, a Henderson man, 39, was charged with possessing methamphetamine for supply, six counts of money laundering and supplying cannabis when he appeared in the dock at 12.45pm.

Police allege he engaged in laundering more than $1.4 million.

The man, who appeared to be out of breath, nodded when Judge Brooke Gibson told him he had interim name suppression until June 29.

He was remanded without plea on bail until June 29.

A 43-year-old Otara man, charged with supplying methamphetamine, was granted interim name suppression and remanded in custody.

Several of those arrested as part of Operation Trojan Shield face charges of participating in an organised crime group.

One of them was a 46-year-old Auckland man who was also granted interim name suppression and remanded on bail until June 29.

He waved from the dock at his supporters in the public gallery before being led back into the cells.

A 65-year-old man from Avondale appeared in the dock shortly before 1pm, charged with supplying meth and money laundering.

He was remanded without plea on bail. Like his co-accused, he will reappear in court on June 29.

A man who faces a string of money laundering charges in relation to Operation Trojan Shield, including being involved in a transaction of $100,000, has been remanded on bail without plea and will appear later this month. He, along with a group of others at Auckland District Court today, has been interim name suppression.

Packed courtroom in Hamilton

In Hamilton, it was standing room only at 3pm as those charged in connection with Operation Trojan Shield were due to appear.

A 20-year-old Hamilton man faced five charges including supplying cocaine, possession of cocaine for supply, possession of methamphetamine for supply, and offering to supply both methamphetamine and cocaine.

He was remanded in custody to reappear via audio visual link on June 29.

Operation Trojan Shield

Operation Trojan Shield targeted the importation, sale and supply of methamphetamine, as well as money-laundering activities, in New Zealand and abroad.

Thirty-five people were arrested after search warrants were executed across New Zealand yesterday and $3.7 million in assets were seized - including cannabis, methamphetamine, iodine, firearms, vehicles, more than $1 million in cash and a number of mobile phones.

Senior members of the Comancheros in Waikato, Mongrel Mob in Waikato and the Head Hunters were among those arrested overnight.

More than 900 charges have been laid. There were still outstanding arrests to be made, National Organised Crime Group director Detective Superintendent Greg Williams said at a press conference this morning.